[Skiboot] [PATCH V6 09/21] core/pldm: Implement PLDM requester
Christophe Lombard
clombard at linux.vnet.ibm.com
Tue Sep 13 20:26:53 AEST 2022
Implement a way for sending PLDM requests for specific PLDM commands.
Send a PLDM request message. Wait for corresponding response message,
which once received, is returned to the caller.
If there's data available, return success only if data is a PLDM response
message that matches instance, pldm_type and command code.
Signed-off-by: Christophe Lombard <clombard at linux.vnet.ibm.com>
---
core/pldm/Makefile.inc | 2 +-
core/pldm/pldm-mctp.c | 9 +-
core/pldm/pldm-requester.c | 331 +++++++++++++++++++++++++++++++++++++
core/pldm/pldm.h | 9 +
4 files changed, 349 insertions(+), 2 deletions(-)
create mode 100644 core/pldm/pldm-requester.c
diff --git a/core/pldm/Makefile.inc b/core/pldm/Makefile.inc
index dbca102a..a9b3b7e6 100644
--- a/core/pldm/Makefile.inc
+++ b/core/pldm/Makefile.inc
@@ -7,7 +7,7 @@ SUBDIRS += $(PLDM_DIR)
CPPFLAGS += -I$(SRC)/pldm/libpldm/
CPPFLAGS += -I$(SRC)/pldm/ibm/libpldm/
-PLDM_OBJS = pldm-mctp.o pldm-responder.o
+PLDM_OBJS = pldm-mctp.o pldm-responder.o pldm-requester.o
PLDM = $(PLDM_DIR)/built-in.a
$(PLDM): $(PLDM_OBJS:%=$(PLDM_DIR)/%)
diff --git a/core/pldm/pldm-mctp.c b/core/pldm/pldm-mctp.c
index 51dbad0a..c7d7bb3b 100644
--- a/core/pldm/pldm-mctp.c
+++ b/core/pldm/pldm-mctp.c
@@ -76,6 +76,8 @@ static int handle_message_rx(uint8_t eid, const uint8_t *buf, int len)
}
switch (rx.hdrinf.msg_type) {
+ case PLDM_RESPONSE:
+ return pldm_requester_handle_response(&rx);
case PLDM_REQUEST:
return pldm_responder_handle_request(&rx);
break;
@@ -120,8 +122,13 @@ int pldm_mctp_init(uint8_t mode)
/* Register mandatory commands we'll respond to */
rc = pldm_responder_init();
- if (rc)
+ if (rc) {
prlog(PR_ERR, "Failed to register mandatory commands\n");
+ goto out;
+ }
+
+ /* Requester implementation */
+ pldm_requester_init();
out:
prlog(PR_NOTICE, "%s - done, rc: %d\n", __func__, rc);
diff --git a/core/pldm/pldm-requester.c b/core/pldm/pldm-requester.c
new file mode 100644
index 00000000..412d495a
--- /dev/null
+++ b/core/pldm/pldm-requester.c
@@ -0,0 +1,331 @@
+// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+// Copyright 2022 IBM Corp.
+
+#define pr_fmt(fmt) "PLDM: " fmt
+
+#include <cpu.h>
+#include <stdio.h>
+#include <string.h>
+#include <timebase.h>
+#include <ast.h>
+#include <pldm/libpldm/utils.h>
+#include "pldm.h"
+
+struct pldm_request {
+ struct list_node link;
+
+ /* originating request params */
+ int dest;
+ int instance;
+ int cmd_code;
+ int type;
+
+ /* messages requested */
+ void *request_msg;
+ int request_len;
+
+ /* timeout handling */
+ struct timer timeout;
+ uint64_t timeout_ms;
+ uint64_t start_time;
+
+ /* completion callback */
+ void (*complete)(struct pldm_rx_data *rx, void *data);
+ void *complete_data;
+};
+
+struct pldm_response {
+ void **response_msg;
+ size_t *response_len;
+ bool done;
+ int rc;
+};
+
+/* pldm requests queue */
+static LIST_HEAD(list_pldm_requests);
+struct lock list_lock;
+struct timer requests_timer;
+
+static struct pldm_request *active_request;
+
+static bool matches_request(const struct pldm_rx_data *rx,
+ const struct pldm_request *req)
+{
+ if (req->instance != rx->hdrinf.instance)
+ return false;
+ if (req->type != rx->hdrinf.pldm_type)
+ return false;
+ if (req->cmd_code != rx->hdrinf.command)
+ return false;
+
+ return true;
+}
+
+static void send_and_wait_complete(struct pldm_rx_data *rx, void *data)
+{
+ struct pldm_response *resp = (struct pldm_response *)data;
+ int len;
+
+ if (rx != NULL) {
+ len = rx->msg_len;
+ *resp->response_len = len;
+ *resp->response_msg = zalloc(len);
+ memcpy(*resp->response_msg, rx->msg, len);
+
+ resp->rc = OPAL_SUCCESS;
+ } else {
+ *resp->response_len = 0;
+ *resp->response_msg = NULL;
+ resp->rc = OPAL_TIMEOUT;
+ }
+
+ resp->done = true;
+}
+
+static void handle_response(struct pldm_rx_data *rx)
+{
+ uint64_t now;
+
+ if (active_request == NULL) {
+ prlog(PR_ERR, "%s: No active request\n", __func__);
+ return;
+ }
+
+ /* unactivate the timer */
+ if (rx != NULL)
+ cancel_timer(&active_request->timeout);
+
+ if (active_request->complete)
+ active_request->complete(rx, active_request->complete_data);
+
+ now = mftb();
+ prlog(PR_TRACE, "%s: Finished after %ldms, t:%d c:%d i:%d \n",
+ __func__,
+ tb_to_msecs(now - active_request->start_time),
+ active_request->type,
+ active_request->cmd_code,
+ active_request->instance);
+
+ free(active_request->request_msg);
+ free(active_request);
+ active_request = NULL;
+}
+
+/*
+ * Timeout :(
+ */
+static void expiry(struct timer *t __unused, void *data, uint64_t now __unused)
+{
+ struct pldm_request *req = (struct pldm_request *)data;
+
+ if (active_request == NULL) {
+ prlog(PR_ERR, "request timedout! (active request NULL)\n");
+ return;
+ }
+
+ prlog(PR_ERR, "request timedout! (active request: t:%d c:%d i:%d)\n",
+ active_request->type,
+ active_request->cmd_code,
+ active_request->instance);
+
+ prlog(PR_TRACE, "%s: Original request t:%d c:%d i:%d -----\n",
+ __func__, req->type, req->cmd_code, req->instance);
+
+ /* no data received. Finish the procedure */
+ handle_response(NULL);
+}
+
+/*
+ * Handle PLDM message received from the PLDM terminus over MCTP
+ */
+int pldm_requester_handle_response(struct pldm_rx_data *rx)
+{
+ /* check the message received */
+ if (active_request == NULL) {
+ prlog(PR_ERR, "%s: No active request. "
+ "Response received t:%d c:%d i:%d\n",
+ __func__,
+ rx->hdrinf.pldm_type,
+ rx->hdrinf.command,
+ rx->hdrinf.instance);
+ return OPAL_WRONG_STATE;
+ }
+
+ if (!matches_request(rx, active_request)) {
+ prlog(PR_ERR, "%s: Unexpected response! t:%d c:%d i:%d want %d,%d,%d\n",
+ __func__,
+ rx->hdrinf.pldm_type,
+ rx->hdrinf.command,
+ rx->hdrinf.instance,
+ active_request->type,
+ active_request->cmd_code,
+ active_request->instance
+ );
+ return OPAL_WRONG_STATE;
+ }
+
+ /* The expected message seems correct */
+ handle_response(rx);
+
+ return OPAL_SUCCESS;
+}
+
+/*
+ * Send the PLDM request
+ */
+static void requests_poller(struct timer *t __unused,
+ void *data __unused,
+ uint64_t now __unused)
+{
+ int rc = OPAL_SUCCESS;
+
+ lock(&list_lock);
+
+ /* no new request to handle */
+ if (list_empty(&list_pldm_requests))
+ goto out;
+
+ /* wait for the end of the processing of the current request */
+ if (active_request)
+ goto out;
+
+ /* remove the first entry in a list */
+ active_request = list_pop(&list_pldm_requests,
+ struct pldm_request,
+ link);
+
+ /* Start timer to control a timeout from the PLDM terminus */
+ init_timer(&active_request->timeout, expiry, active_request);
+ schedule_timer(&active_request->timeout,
+ msecs_to_tb(active_request->timeout_ms));
+ active_request->start_time = mftb();
+
+ /* Send PLDM message over MCTP */
+ prlog(PR_TRACE, "%s: Sending request to BMC t:%d c:%d i:%d -----\n",
+ __func__,
+ active_request->type,
+ active_request->cmd_code,
+ active_request->instance);
+
+ rc = pldm_mctp_message_tx(active_request->dest,
+ active_request->request_msg,
+ active_request->request_len);
+ if (rc)
+ prlog(PR_ERR, "%s: Error %d while sending request\n",
+ __func__, rc);
+
+out:
+ unlock(&list_lock);
+ schedule_timer(&requests_timer, msecs_to_tb(5));
+}
+
+/*
+ * Add PLDM request in the queue
+ */
+static int queue_request(void *request_msg, int request_len,
+ uint64_t timeout_ms,
+ void (*complete)(struct pldm_rx_data *rx, void *data),
+ void *complete_data)
+{
+ struct pldm_header_info hdrinf;
+ struct pldm_request *pending;
+
+ if (unpack_pldm_header(request_msg, &hdrinf)) {
+ prlog(PR_ERR, "%s: error parsing pldm header\n",
+ __func__);
+ return OPAL_PARAMETER;
+ }
+
+ pending = zalloc(sizeof(struct pldm_request));
+
+ pending->dest = BMC_EID;
+ pending->instance = hdrinf.instance;
+ pending->type = hdrinf.pldm_type;
+ pending->cmd_code = hdrinf.command;
+ pending->timeout_ms = timeout_ms;
+ pending->request_msg = zalloc(request_len);
+ memcpy(pending->request_msg, request_msg, request_len);
+
+ pending->request_len = request_len;
+ pending->complete = complete;
+ pending->complete_data = complete_data;
+
+ /* add an entry at the end of a linked list */
+ lock(&list_lock);
+ prlog(PR_TRACE, "%s: Add request t:%d c:%d i:%d -----\n",
+ __func__,
+ pending->type,
+ pending->cmd_code,
+ pending->instance);
+ list_add_tail(&list_pldm_requests, &pending->link);
+ unlock(&list_lock);
+
+ return OPAL_SUCCESS;
+}
+
+#define TIMEOUT_MS 8000
+
+/*
+ * Queue a PLDM request and don't wait.
+ * When a response is received, call the associated callback.
+ */
+int pldm_requester_queue(void *request_msg, size_t request_len,
+ void (*complete)(struct pldm_rx_data *rx, void *data),
+ void *complete_data)
+{
+ int rc = OPAL_SUCCESS;
+
+ rc = ast_mctp_ready();
+ if (rc) {
+ prlog(PR_ERR, "%s: BMC is not listening (rc: %d)\n",
+ __func__, rc);
+ return rc;
+ }
+
+ /* Queue PLDM request */
+ rc = queue_request(request_msg, request_len,
+ TIMEOUT_MS, complete,
+ complete_data);
+ if (rc) {
+ prlog(PR_ERR, "%s: Error %d while queuing request\n",
+ __func__, rc);
+ return rc;
+ }
+
+ return rc;
+}
+
+/*
+ * Queue a PLDM request and spin until we get a response.
+ */
+int pldm_requester_queue_and_wait(void *request_msg, size_t request_len,
+ void **response_msg, size_t *response_len)
+{
+ struct pldm_response resp;
+ int rc;
+
+ memset(&resp, 0, sizeof(resp));
+ resp.response_msg = response_msg;
+ resp.response_len = response_len;
+
+ rc = pldm_requester_queue(request_msg, request_len,
+ send_and_wait_complete, &resp);
+ if (rc)
+ return rc;
+
+ /* wait for a response from the BMC */
+ do {
+ time_wait_ms(5);
+ } while (!resp.done);
+
+ return resp.rc;
+}
+
+void pldm_requester_init(void)
+{
+ /* lock used to queue and unqueue pldm requests */
+ init_lock(&list_lock);
+
+ init_timer(&requests_timer, requests_poller, NULL);
+ schedule_timer(&requests_timer, msecs_to_tb(5));
+}
diff --git a/core/pldm/pldm.h b/core/pldm/pldm.h
index 7df413da..fa7a80de 100644
--- a/core/pldm/pldm.h
+++ b/core/pldm/pldm.h
@@ -42,4 +42,13 @@ int pldm_mctp_message_tx(uint8_t dest_id, uint8_t *buf, int len);
int pldm_responder_handle_request(struct pldm_rx_data *rx);
int pldm_responder_init(void);
+/* Requester support */
+int pldm_requester_handle_response(struct pldm_rx_data *rx);
+int pldm_requester_queue(void *request_msg, size_t request_len,
+ void (*complete)(struct pldm_rx_data *rx, void *data),
+ void *complete_data);
+int pldm_requester_queue_and_wait(void *request_msg, size_t request_len,
+ void **response_msg, size_t *response_len);
+void pldm_requester_init(void);
+
#endif /* __COREPLDM_H__ */
--
2.37.3
More information about the Skiboot
mailing list